Placental structural abnormalities in gestational diabetes and when they develop: A scoping review

Gestational diabetes mellitus and development of intergenerational overall and subtypes of cardiovascular diseases: a systematic review and meta-analysis

OBJECTIVE

We aimed to summarize the association between gestational diabetes mellitus (GDM) and its intergenerational cardiovascular diseases (CVDs) impacts in both mothers and offspring post-delivery in existing literature.

METHODS

PubMed, Embase, Web of Science, and Scopus were utilized for searching publications between January 1980 and June 2024, with data extraction and meta-analysis continuing until 31 July 2024. Based on a predefined PROSPERO protocol, studies published as full-length, English-language journal articles that reported the presence of GDM during pregnancy and its association with any CVD development post-delivery were selected. All studies were evaluated using the Newcastle-Ottawa Scale. Maximally adjusted risk estimates were pooled using random-effects meta-analysis to assess the risk ratio (RR) of GDM, and overall and subtypes of CVDs in both mothers and offspring post-delivery.

RESULTS

The meta-analysis was based on 38 studies with a total of 77,678,684 participants. The results showed a 46% increased risk (RR 1.46, 95% CI 1.34-1.59) for mothers and a 23% increased risk (1.23, 1.05-1.45) for offspring of developing overall CVDs after delivery, following a GDM-complicated pregnancy. Our subgroup analysis revealed that mothers with a history of GDM faced various risks (20% to 2-fold) of developing different subtypes of CVDs, including cerebrovascular disease, coronary artery disease, heart failure, and venous thromboembolism.

CONCLUSIONS

These findings underscore the heightened risk of developing various CVDs for mothers and offspring affected by GDM, emphasizing the importance of preventive measures even right after birth to mitigate the burden of CVDs in these populations.

Pathophysiology from preconception, during pregnancy, and beyond

Gestational diabetes is the most common medical complication in pregnancy. Historically, gestational diabetes was considered a pregnancy complication involving treatment of rising glycaemia late in the second trimester. However, recent evidence challenges this view. Pre-pregnancy and pregnancy-specific factors influence gestational glycaemia, with open questions regarding roles of non-glycaemic factors in the aetiology and consequences of gestational diabetes. Varying patterns of insulin secretion and resistance in early and late pregnancy underlie a heterogeneity of gestational diabetes in the timing and pathophysiological subtypes with clinical implications: early gestational diabetes and insulin resistant gestational diabetes subtypes are associated with a higher risk of pregnancy complications. Metabolic perturbations of early gestational diabetes can affect early placental development, affecting maternal metabolism and fetal development. Fetal hyperinsulinaemia can affect the development of multiple fetal tissues, with short-term and long-term consequences. Pregnancy complications are prevented by managing glycaemia in early and late pregnancy in some, but not all women with gestational diabetes. A better understanding of the pathophysiology and heterogeneity of gestational diabetes will help to develop novel management approaches with focus on improved prevention of maternal and offspring short-term and long-term complications, from pre-conception, throughout pregnancy, and beyond.

Mutual effects of gestational diabetes and schizophrenia: how can one promote the other?: A review

Although the physical complications of gestational diabetes mellitus (GDM) are well known, emerging evidence suggests a significant link with psychiatric conditions such as schizophrenia (SCZ). This review aimed to explore the extent, nature, and implications of the association between GDM and SCZ, exploring how the 2 conditions may reciprocally influence each other. We conducted a comprehensive literature review and, analyzed clinical and mechanistic evidence supporting the mutual effects of GDM and SCZ. This review examined factors such as neurodevelopment and the impact of antipsychotics. The study found that Maternal GDM increases the risk of SCZ in offspring. Conversely, women with SCZ were more prone to hyperglycemic pregnancies. The research highlights significant regional variations in GDM prevalence, with the highest rate in the Middle East, North Africa, and South-East Asia regions. These regional variations may have an impact on the epidemiology of SCZ. Furthermore, this review identifies the potential biological and environmental mechanisms underlying these associations. There is a bidirectional relationship between GDM and SCZ, with each disorder potentially exacerbating the others. This relationship has significant implications for maternal and offspring health, particularly in regions with high GDM prevalence. These findings underline the need for integrated care approaches for women with SCZ during pregnancy and the importance of monitoring and managing GDM to mitigate the risk of SCZ in the offspring. Notably, this study recognizes the need for further research to fully understand these complex interactions and their implications for healthcare.

Morphometric Analysis of Placenta and Fetal Doppler Indices in Normal and High-Risk Pregnancies

Background High-risk pregnancies, encompassing pregnancy-induced hypertension (PIH), gestational diabetes mellitus (GDM), preeclampsia toxemia (PET), and intrauterine growth restriction (IUGR), represent intricate medical challenges with potential repercussions for maternal and fetal health. This research undertakes a comprehensive comparative investigation into the variations of Doppler indices and placental parameters within the context of these high-risk conditions when juxtaposed against pregnancies characterized as normal. Methodology Employing a rigorous cross-sectional study design, a diverse cohort of pregnant individuals with gestational diabetes, IUGR, PIH, and preeclampsia was meticulously assembled. Additionally, a group of normal pregnant women served as the comparative reference. Doppler ultrasound assessments, viz, pulsatility index (PI), were carefully performed to estimate blood flow velocities within critical maternal and fetal vessels, while placental parameters were meticulously quantified, encompassing dimensions, vascular architecture, and morphological features. Results Except in the GDM group, all high-risk groups had reduced estimated placental weight and actual birth weight than normal pregnant women. All high-risk groups showed a highly significant elevation of the PI of the umbilical artery and PI of the middle cerebral artery (MCA) than normal but the PI of MCA was significantly reduced in the PET group than in normal individuals. The cerebro-placental ratio in the GDM and IUGR groups revealed markedly greater values, whereas PET showed lower values. IUGR and PIH groups showed a substantial reduction in the fetal birth weight. All high-risk groups (GDM, IUGR, PIH, and PET) showed a highly significant reduction in luminal area umbilical artery 1 than the normal pregnant women. In IUGR, marginal placental insertion was very high, followed by GDM and PET groups. Conclusions This study reveals that Doppler indices, placental parameters, newborn weight, and their related ratios may be utilized to anticipate gestation difficulties and gain insight into the pathophysiology of problematic conceptions.

The Placental Role in Gestational Diabetes Mellitus: A Molecular Perspective

During pregnancy, women undergo several metabolic changes to guarantee an adequate supply of glucose to the foetus. These metabolic modifications develop what is known as physiological insulin resistance. When this process is altered, however, gestational diabetes mellitus (GDM) occurs. GDM is a multifactorial disease, and genetic and environmental factors play a crucial role in its aetiopathogenesis. GDM has been linked to both macroscopic and molecular alterations in placental tissues that affect placental physiology. This review summarizes the role of the placenta in the development of GDM from a molecular perspective, including hormonal and pro-inflammatory changes. Inflammation and hormonal imbalance, the characteristics dominating the GDM microenvironment, are responsible for placental changes in size and vascularity, leading to dysregulation in maternal and foetal circulations and to complications in the newborn. In conclusion, since the hormonal mechanisms operating in GDM have not been fully elucidated, more research should be done to improve the quality of life of patients with GDM and their future children.

Changes of miR-139-5p, TGFB1, and COL1A1 in the placental tissue of cases with gestational diabetes mellitus

There are structural changes in the placenta of cases with Gestational Diabetes Mellitus (GDM). TGF-β and collagen pathways have crucial roles in tissue remodeling and TGF-β1 and COL1A1 are important genes in these signalling respectively. Also, lncRNA NEAT1, and miRNA hsa-miR-139-5p and hsa-miR-129-5p have regulatory effects on TGF-β1 and COL1A1. Here we aimed to assess their expressions in the placenta tissue of GDM cases. 30 patients with GDM and 30 healthy pregnant women participated in the study. Placental tissues taken during normal or cesarean delivery were used and total RNA was isolated from the tissues. mRNA levels were determined by qPCR and protein levels were determined by ELISA methods. An in silico analysis was done to elucidate the possible relation of TGF-β1 and COL1A1 gene networks with GDM. We determined that NEAT1 and miR-129-5p expression levels did not differ between GDM and healthy control groups (p = 0.697 and 0.412, respectively). But, miR-139-5p mRNA level, TGFB1 and COL1A1 protein levels significantly differ between the GDM and control groups (p = 0.000, p = 0.000 and p = 0.001, respectively). The in silico analysis revealed that TGFB1 and COL1A1 genes network may have important role in the GDM with their variety of members and regulatory molecules NEAT1, hsa-miR-139-5p, and hsa-miR-129-5p can control their functions. The expression of TGFB1, COL1A1 and miR-139-5p is changed in placenta tissue of GDM cases and many genes in the interacting networks of TGFB1 and COL1A1 could contribute to the pathogenicity of GDM.

The association between human chorionic gonadotropin and adverse pregnancy outcomes: a systematic review and meta-analysis

OBJECTIVE

This study aimed to evaluate the association between human chorionic gonadotropin and adverse pregnancy outcomes.

DATA SOURCES

Medline, Embase, PubMed, and Cochrane were searched in November 2021 using Medical Subject Headings (MeSH) and relevant key words.

STUDY ELIGIBILITY CRITERIA

This analysis included published full-text studies of pregnant women with serum human chorionic gonadotropin testing between 8 and 28 weeks of gestation, investigating fetal outcomes (fetal death in utero, small for gestational age, preterm birth) or maternal factors (hypertension in pregnancy: preeclampsia, pregnancy-induced hypertension, placental abruption, HELLP syndrome, gestational diabetes mellitus).

METHODS

Studies were extracted using REDCap software. The Newcastle-Ottawa scale was used to assess for risk of bias. Final meta-analyses underwent further quality assessment using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) method.

RESULTS

A total of 185 studies were included in the final review, including the outcomes of fetal death in utero (45), small for gestational age (79), preterm delivery (62), hypertension in pregnancy (107), gestational diabetes mellitus (29), placental abruption (17), and HELLP syndrome (2). Data were analyzed separately on the basis of categorical measurement of human chorionic gonadotropin and human chorionic gonadotropin measured on a continuous scale. Eligible studies underwent meta-analysis to generate a pooled odds ratio (categorical human chorionic gonadotropin level) or difference in medians (human chorionic gonadotropin continuous scale) between outcome groups. First-trimester low human chorionic gonadotropin levels were associated with preeclampsia and fetal death in utero, whereas high human chorionic gonadotropin levels were associated with preeclampsia. Second-trimester high human chorionic gonadotropin levels were associated with fetal death in utero and preeclampsia.

CONCLUSION

Human chorionic gonadotropin levels are associated with placenta-mediated adverse pregnancy outcomes. Both high and low human chorionic gonadotropin levels in the first trimester of pregnancy can be early warning signs of adverse outcomes. Further analysis of human chorionic gonadotropin subtypes and pregnancy outcomes is required to determine the diagnostic utility of these findings in reference to specific cutoff values.

Gestational diabetes mellitus and adverse maternal and perinatal outcomes in twin and singleton pregnancies: a systematic review and meta-analysis

OBJECTIVE

This study aimed to assess the risk of adverse maternal and perinatal complications between twin and singleton pregnancies affected by gestational diabetes mellitus and the respective group without gestational diabetes mellitus (controls).

DATA SOURCES

A literature search was performed using MEDLINE, Embase, and Cochrane from January 1980 to May 2023.

STUDY ELIGIBILITY CRITERIA

Observational studies reporting maternal and perinatal outcomes in singleton and/or twin pregnancies with gestational diabetes mellitus vs controls were included.

METHODS

This was a systematic review and meta-analysis. Pooled estimate risk ratios with 95% confidence intervals were generated to determine the likelihood of adverse pregnancy outcomes between twin and singleton pregnancies with and without gestational diabetes mellitus. Heterogeneity among studies was evaluated in the model and expressed using the I2 statistic. A P value of <.05 was considered statistically significant. The meta-analyses were performed using Review Manager (RevMan Web). Version 5.4. The Cochrane Collaboration, 2020. Meta-regression was used to compare relative risks between singleton and twin pregnancies. The addition of multiple covariates into the models was used to address the lack of adjustments.

RESULTS

Overall, 85 studies in singleton pregnancies and 27 in twin pregnancies were included. In singleton pregnancies with gestational diabetes mellitus, compared with controls, there were increased risks of hypertensive disorders of pregnancy (relative risk, 1.85; 95% confidence interval, 1.69-2.01), induction of labor (relative risk, 1.36; 95% confidence interval, 1.05-1.77), cesarean delivery (relative risk, 1.31; 95% confidence interval, 1.24-1.38), large-for-gestational-age neonate (relative risk, 1.61; 95% confidence interval, 1.46-1.77), preterm birth (relative risk, 1.36; 95% confidence interval, 1.27-1.46), and admission to the neonatal intensive care unit (relative risk, 1.43; 95% confidence interval, 1.38-1.49). In twin pregnancies with gestational diabetes mellitus, compared with controls, there were increased risks of hypertensive disorders of pregnancy (relative risk, 1.69; 95% confidence interval, 1.51-1.90), cesarean delivery (relative risk, 1.10; 95% confidence interval, 1.06-1.13), large-for-gestational-age neonate (relative risk, 1.29; 95% confidence interval, 1.03-1.60), preterm birth (relative risk, 1.19; 95% confidence interval, 1.07-1.32), and admission to the neonatal intensive care unit (relative risk, 1.20; 95% confidence interval, 1.09-1.32) and reduced risks of small-for-gestational-age neonate (relative risk, 0.89; 95% confidence interval, 0.81-0.97) and neonatal death (relative risk, 0.50; 95% confidence interval, 0.39-0.65). When comparing relative risks in singleton vs twin pregnancies, there was sufficient evidence to suggest that twin pregnancies have a lower relative risk of cesarean delivery (P=.003), have sufficient adjustment for confounders, and have lower relative risks of admission to the neonatal intensive care unit (P=.005), stillbirths (P=.002), and neonatal death (P=.001) than singleton pregnancies.

CONCLUSION

In both singleton and twin pregnancies, gestational diabetes mellitus was associated with an increased risk of adverse maternal and perinatal outcomes. In twin pregnancies, gestational diabetes mellitus may have a milder effect on some adverse perinatal outcomes and may be associated with a lower risk of neonatal death.

Crosstalk between inflammasomes, inflammation, and Nrf2: Implications for gestational diabetes mellitus pathogenesis and therapeutics

The role of inflammasomes in gestational diabetes mellitus (GDM) has emerged as a critical area of research in recent years. Inflammasomes, key components of the innate immune system, are now recognized for their involvement in the pathogenesis of GDM. Activation of inflammasomes in response to various triggers during pregnancy can produce pro-inflammatory cytokines, such as interleukin-1β (IL-1β) and interleukin-18 (IL-18), contributing to systemic inflammation and insulin resistance. This dysregulation not only impacts maternal health but also poses significant risks to fetal development and long-term health outcomes. Understanding the intricate interplay between inflammasomes and GDM holds promise for developing novel therapeutic strategies and interventions to mitigate the adverse effects of this condition on both mothers and their offspring. Researchers have elucidated that targeting inflammasomes using anti-inflammatory drugs and compounds can effectively reduce inflammation in GDM. Furthermore, the addition of nuclear factor erythroid 2-related factor 2 (Nrf2) to this complex mechanism opens novel avenues for therapeutics. The antioxidant properties of Nrf2 may potentially suppress inflammasome activation in GDM. This comprehensive review investigates the intricate relationship between inflammasomes and GDM, emphasizing the pivotal role of inflammation in its pathogenesis. It also sheds light on potential therapeutic strategies targeting inflammasome activation and explores the role of Nrf2 in mitigating inflammation in GDM.

Relationship Between Anatomic Features of the Placenta, the Type of Abnormal Placental Cord Insertion and Adverse Pregnancy Outcomes in Singleton Pregnancies: A Prospective Observational Study

INTRODUCTION

This study aimed to evaluate the potential value of placental anatomic features and various types of normal and abnormal cord insertion types in predicting adverse maternal-fetal outcomes in singleton pregnancies. We also tried to assess the association between these outcomes and various types of placental cord insertion.

METHOD

This prospective observational study was performed on singleton pregnancies. For each patient placental features including diameter, thickness, type of cord insertion, and the shortest distance between the cord insertion point and placental edge were recorded. The relationship between these factors and the development of multiple adverse pregnancy outcomes including preterm labor, intrauterine fetal death (IUFD), and the rate of neonatal intensive care unit (NICU) admissions were evaluated and reported.

RESULTS

Overall 308 patients were enrolled in the study. Smoker mothers had significantly smaller placentas (P-value = .008), and those with lower diameter placentas were more likely to suffer from IUFD (P-value = .0001). Shorter placental cord insertion distances led to more episodes of preterm labor (P-value = .057). Eccentric-type placental cord insertion was significantly associated with the development of preeclampsia (P-value = .006).

DISCUSSION

Abnormalities in placental diameter and cord insertion can lead to significant maternal-fetal complications including preterm labor, IUFD, and preeclampsia.

Placental pathologic features in obesity

INTRODUCTION

Obesity in pregnancy is associated with adverse long-term consequences both in the mother and in offspring. Maternal obesity induces a metabolic-inflammatory state that could impact on placental function and could mediate the adverse outcomes. The purpose of this study was to compare the major placental histological characteristics of non-diabetic obese women to lean controls, focusing on uncomplicated pregnancies.

METHODS

Prospective case-control study comparing placental histopathological features between 122 non-diabetic obese women and 185 non-obese controls. The analysis was performed on overall subjects, then uncomplicated pregnancies from both groups were analyzed. Placenta pathologic findings were recorded according to standard classification.

RESULTS

Both in overall analysis and among the subset of subjects with an uncomplicated pregnancy, obese subjects had higher risks of maternal vascular malperfusion (MVM) (respectively OR=2.2, 95%CI =1.3-3.7 and OR=4.2, 95%CI=2.1-8.5), fetal vascular malperfusion (FVM) (respectively OR=6.3, 95%CI=3.1-12.5 and OR=7.2, 95%CI=3-17.2), maternal and fetal inflammatory response placental lesions and villitis (VUE) (respectively OR=2.5, 95%CI=1.1-5.6 and OR=10.8, 95%CI=3.3-35.3) compared to controls. Among uncomplicated pregnancies and after adjustment for confounders, first trimester BMI was significantly associated with overall MVM, overall FVM, maternal inflammatory, fetal inflammatory response and VUE.

DISCUSSION

Placentas from obese women showed a significantly higher risk of maternal and fetal vascular and inflammatory placental lesions, both in overall population and in the subgroup with uncomplicated pregnancies. The metabolic and inflammatory dysfunctions typical of obesity could have an impact on placental development and function, which could be a mediator of the detrimental effects of obesity on pregnancy outcome and on future health of the offspring.

GMRLNet: A Graph-Based Manifold Regularization Learning Framework for Placental Insufficiency Diagnosis on Incomplete Multimodal Ultrasound Data

Multimodal analysis of placental ultrasound (US) and microflow imaging (MFI) could greatly aid in the early diagnosis and interventional treatment of placental insufficiency (PI), ensuring a normal pregnancy. Existing multimodal analysis methods have weaknesses in multimodal feature representation and modal knowledge definitions and fail on incomplete datasets with unpaired multimodal samples. To address these challenges and efficiently leverage the incomplete multimodal dataset for accurate PI diagnosis, we propose a novel graph-based manifold regularization learning (MRL) framework named GMRLNet. It takes US and MFI images as input and exploits their modality-shared and modality-specific information for optimal multimodal feature representation. Specifically, a graph convolutional-based shared and specific transfer network (GSSTN) is designed to explore intra-modal feature associations, thus decoupling each modal input into interpretable shared and specific spaces. For unimodal knowledge definitions, graph-based manifold knowledge is introduced to describe the sample-level feature representation, local inter-sample relations, and global data distribution of each modality. Then, an MRL paradigm is designed for inter-modal manifold knowledge transfer to obtain effective cross-modal feature representations. Furthermore, MRL transfers the knowledge between both paired and unpaired data for robust learning on incomplete datasets. Experiments were conducted on two clinical datasets to validate the PI classification performance and generalization of GMRLNet. State-of-the-art comparisons show the higher accuracy of GMRLNet on incomplete datasets. Our method achieves 0.913 AUC and 0.904 balanced accuracy (bACC) for paired US and MFI images, as well as 0.906 AUC and 0.888 bACC for unimodal US images, illustrating its application potential in PI CAD systems.

Extracellular vesicle-mediated targeting strategies for long-term health benefits in gestational diabetes

Extracellular vesicles (EVs) are critical mediators of cell communication, playing important roles in regulating molecular cross-talk between different metabolic tissues and influencing insulin sensitivity in both healthy and gestational diabetes mellitus (GDM) pregnancies. The ability of EVs to transfer molecular cargo between cells imbues them with potential as therapeutic agents. During pregnancy, the placenta assumes a vital role in metabolic regulation, with multiple mechanisms of placenta-mediated EV cross-talk serving as central components in GDM pathophysiology. This review focuses on the role of the placenta in the pathophysiology of GDM and explores the possibilities and prospects of targeting the placenta to address insulin resistance and placental dysfunction in GDM. Additionally, we propose the use of EVs as a novel method for targeted therapeutics in treating the dysfunctional placenta. The primary aim of this review is to comprehend the current status of EV targeting approaches and assess the potential application of these strategies in placental therapeutics, thereby delivering molecular cargo and improving maternal and fetal outcomes in GDM. We propose that EVs have the potential to revolutionize GDM management, offering hope for enhanced maternal-fetal health outcomes and more effective treatments.

Diabetes-related perturbations in the integrity of physiologic barriers

One of the hallmarks of health is the integrity of barriers at the cellular and tissue levels. The two cardinal functions of barriers include preventing access of deleterious elements of the environment (barrier function) while facilitating the transport of essential ions, signaling molecules and nutrients needed to maintain the internal milieu (transport function). There are several cellular and subcellular barriers and some of these barriers can be interrelated. The principal physiologic barriers include blood-retinal barrier, blood-brain barrier, blood-testis barrier, renal glomerular/tubular barrier, intestinal barrier, pulmonary blood-alveolar barrier, blood-placental barrier and skin barrier. Tissue specific barriers are the result of the vasculature, cellular composition of the tissue and extracellular matrix within the tissue. Uncontrolled diabetes and acute hyperglycemia may disrupt the integrity of physiologic barriers, primarily through altering the vascular integrity of the tissues and may well contribute to the clinically recognized complications of diabetes. Although diabetes is a systemic disease, some of the organs display clinically significant deterioration in function while others undergo subclinical changes. The pathophysiology of the disruption of these barriers is not entirely clear but it may be related to diabetes-related cellular stress. Understanding the mechanisms of diabetes related dysfunction of various physiologic barriers might help identifying novel therapeutic targets for reducing clinically significant complications of diabetes.

The impact of polycystic ovary syndrome on placental histopathology patterns in in-vitro fertilization singleton live births

INTRODUCTION

Pregnant polycystic ovary syndrome (PCOS) patients are at increased risk for myriad obstetric complications, with the placenta thought to play a key role in their development. We aimed to evaluate placental histopathology patterns in placentas of women with PCOS who underwent in-vitro-fertilization (IVF).

METHODS

This retrospective study utilized full gross and histopathologic assessment of placentas of all women who had IVF treatment and delivered at the Royal Victoria Hospital from 2009 to 2017, regardless of complications or mode of delivery. Pathologic findings included anatomic, inflammation, villous maturation, and vascular mal-perfusion features. Placentas of PCOS women were compared to those of ovulatory controls. Multivariate logistic regression was used to adjust results for confounding factors potentially associated with significant placental and perinatal characteristics.

RESULTS

Women with PCOS (n = 47) were more likely to develop gestational diabetes mellitus compared to ovulatory controls (n = 1121) (38.3% vs. 9.8%, p < 0.001). Placentas from PCOS women were more likely circumvallate placentas (aOR 8.3, 95%CI 1.9-37.3) and more likely to have a hypercoiled umbilical cord (aOR 6.8 95%CI 1.3-36.8) and villitis of unknown etiology (aOR 6.1, 95%CI 1.5-25.6). There was an increased likelihood of chorangiosis (aOR 2.7, 95% CI 1.3-5.8), evidence of fetal vascular malperfusion based on one criteria (aOR 2.7, 95%CI 1.1-7.4), or more than one criteria (aOR 6.4, 95%CI 1.6-25.9), more nucleated fetal red blood cells (aOR 5.2, 95%CI 1.1-24.5), and a higher likelihood of chorangiomas (aOR 9.4, 95%CI 1.6-55.1) in placentas from PCOS women than in controls.

DISCUSSION

IVF pregnancies' placental histopathological characteristics are significantly impacted by an underlying diagnosis of PCOS, including important anatomic changes and vascular placental abnormalities.

Comparative study of microvascular structural changes in the gestational diabetic placenta

AIMS

Microvascular morphology and pathological changes in gestational diabetes mellitus (GDM) placentas and normal placentas were observed via vascular casting technology, electron microscopy, and pathological detection technology. Vascular structure and histological morphology changes in GDM placentas were examined to generate basic experimental data for the diagnosis and prognostic determination of GDM.

METHODS

This case-control study involving 60 placentas, 30 from healthy controls and 30 from patients with GDM. Differences in size, weight, volume, umbilical cord diameter, and gestational age were assessed. Histological changes in the placentas in the two groups were analyzed and compared. A placental vessel casting model was constructed using a self-setting dental powder technique, to compare the two groups. The placental cast microvessels of the two groups were compared using scanning electron microscopy.

RESULTS

There were no significant differences in maternal age or gestational age between the GDM group and the control group (p > .05). The size, weight, volume, and thickness of the placentas in the GDM group were significantly greater than those in the control group, as was umbilical cord diameter (p < .05). Immature villus, fibrinoid necrosis, calcification, and vascular thrombosis were significantly greater in the placental mass in the GDM group (p < .05). The terminal branches of the microvessels in diabetic placenta casts were sparse, with significantly fewer ends and lower villous volume (p < .05).

CONCLUSION

Gestational diabetes can cause gross and histological changes in the placenta, particularly placental microvascular changes.

Ambient air pollution and gestational diabetes mellitus: An updated systematic review and meta-analysis

OBJECTIVE

We aimed to evaluate the relationship between the composition of particulate matter (PM) and gestational diabetes mellitus (GDM) by a comprehensively review of epidemiological studies.

METHODS

We systematically identified cohort studies related to air pollution and GDM risk before February 8, 2023 from six databases (PubMed, Embase, Web of Science Core Collection, China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform and Chongqing VIP Chinese Science and Technology Periodical databases). We calculated the relative risk (RR) and its 95% confidence intervals (CIs) to assess the overall effect by using a random effects model.

RESULTS

This meta-analysis of 31 eligible cohort studies showed that exposure to PM_2.5, PM₁₀, SO₂, and NO₂ was associated with a significantly increased risk of GDM, especially in preconception and first trimester. Analysis of the components of PM_2.5 found that the risk of GDM was strongly linked to black carbon (BC) and nitrates (NO₃^-). Specifically, BC exposure in the second trimester and NO₃^- exposure in the first trimester elevated the risk of GDM, with the RR of 1.128 (1.032-1.231) and 1.128 (1.032-1.231), respectively. The stratified analysis showed stronger correlations of GDM risk with higher levels of pollutants in Asia, except for PM_2.5 and BC, which suggested that the specific composition of particulate pollutants had a greater effect on the exposure-outcome association than the concentration.

CONCLUSIONS

Our study found that ambient air pollutant is a critical factor for GDM and further studies on specific particulate matter components should be considered in the future.

High TXNIP expression accelerates the migration and invasion of the GDM placenta trophoblast

INTRODUCTION

Our previous study has proofed the glucose sensitive gene-thioredoxin-interacting protein (TXNIP) expression was up in the placenta of the patients with gestational diabetes mellitus (GDM), but the pathological mechanisms underlying abnormal TXNIP expression in the placenta of patients with GDM is completely unclear and additional investigations are required to explain the findings we have observed. In the present study, we simulated the high TXNIP expression via introducing the Tet-On "switch" in vitro, approximate to its expression level in the real world, to explore the following consequence of the abnormal TXNIP.

METHODS

The expression and localization of TXNIP in the placenta of GDM patients and the health control was investigated via immunofluorescent staining, western blot and RT-qPCR. Overexpression of TXNIP was achieved through transfecting Tet-on system to the human trophoblastic cell line-HTR-8/Svneo cell. TXNIP knockout was obtained via CRISPR-Cas9 method. The cell phenotype was observed via IncuCyte Imaging System and flow cytometry. The mechanism was explored via western blot and RT-qPCR.

RESULTS

The expression level of TXNIP in the GDM placenta was nearly 2-3 times higher than that in the control. The TXNIP located at trophoblastic cells of the placenta. When the expression of TXNIP was upregulated, the migration and invasion of the cells accelerated, but cell apoptosis and proliferation did not changed compared with the control group. Furthermore, the size of the TetTXNIP cells became larger, and the expression level of Vimentin and p-STAT3 increased in the TetTXNIP cells. All the changes mentioned above were opposite in the TXNIP-KO cells.

CONCLUSIONS

Abnormal expression of TXNIP might be related to the impairment of the GDM placental function, affecting the migration and invasion of the placental trophoblast cells through STAT3 and Vimentin related pathway; thus, TXNIP might be the potential therapeutic target for repairing the placental dysfunction deficient in GDM patients.

Thyroid dysfunction during gestation and gestational diabetes mellitus: a complex relationship

PURPOSE

Gestational diabetes mellitus (GDM) and thyroid dysfunction during gestation (GTD) are the two most prevalent endocrinopathies during pregnancy. The aim of the present review is to provide an overview of the peculiar aspects of GDM and GTD, to highlight the potential interactions and clinical consequences of these two frequent clinical conditions.

METHODS

A literature review regarding GDM and GTD was carried out with particular interest on meta-analyses and human studies dealing with the (i) shared risk factors between GDM and GTD, (ii) the epidemiological link between GTD and GDM, (iii) physiopathologic link between GTD and GDM, (iv) clinical consequences of GDM and GTD, and (v) post-partum implications of GDM and GTD.

RESULTS

The association between GDM and GTD is common and may be explained by the insulin-resistance state due to maternal GTD, to alterations in the placentation process or to the many shared risk factors. Discrepant results of epidemiologic studies can be explained, at least in part, by the changes in diagnostic criteria and screening strategies throughout the years for both conditions. GDM and GTD impact pregnancy outcome and have post-partum long-term consequences, but more studies are needed to prove an additional adverse effect.

CONCLUSIONS

Based on the epidemiological and physio-pathological link between GDM and GTD, it could be suggested that a diagnosis of GTD could lead to screen GDM and the other way round.

Ca2+-Activated K+ Channels and the Regulation of the Uteroplacental Circulation

Adequate uteroplacental blood supply is essential for the development and growth of the placenta and fetus during pregnancy. Aberrant uteroplacental perfusion is associated with pregnancy complications such as preeclampsia, fetal growth restriction (FGR), and gestational diabetes. The regulation of uteroplacental blood flow is thus vital to the well-being of the mother and fetus. Ca²⁺-activated K⁺ (K_Ca) channels of small, intermediate, and large conductance participate in setting and regulating the resting membrane potential of vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) and play a critical role in controlling vascular tone and blood pressure. K_Ca channels are important mediators of estrogen/pregnancy-induced adaptive changes in the uteroplacental circulation. Activation of the channels hyperpolarizes uteroplacental VSMCs/ECs, leading to attenuated vascular tone, blunted vasopressor responses, and increased uteroplacental blood flow. However, the regulation of uteroplacental vascular function by K_Ca channels is compromised in pregnancy complications. This review intends to provide a comprehensive overview of roles of K_Ca channels in the regulation of the uteroplacental circulation under physiological and pathophysiological conditions.

Three-dimensional morphological revealing of human placental villi with common obstetric complications via optical coherence tomography

Placental villi play a vital role in human fetal development, acting as the bridge of material exchange between the maternal and fetal. The abnormal morphology of placental villi is closely related to placental circulation disorder and pregnancy complications. Revealing placental villi three-dimensional (3D) morphology of common obstetric complications and healthy pregnancies provides a new perspective for studying the role of the placenta and its villi in the development of pregnancy diseases. In this study, we established a noninvasive, high-resolution 3D imaging platform via optical coherence tomography to reveal placental villi 3D morphological information of diseased and normal placentae. For the first time, 3D morphologies of placental villous tree structures in common obstetric complications were quantitatively revealed and corresponding 3D information could visualize the morphological characteristics of the placental villous tree from a more intuitive perspective, providing helpful information to the study of fetal development, feto-maternal material exchange, and gestational complications treatment.

Gestational diabetes mellitus in in-vitro fertilization pregnancies - Clinical and placental histological characteristics

INTRODUCTION

We aimed to investigate obstetric and neonatal outcomes and placental histological findings in in vitro fertilization (IVF) pregnancies complicated by gestational diabetes mellitus (GDM) as compared to unassisted pregnancies.

METHODS

This was a retrospective cohort of deliveries at a single university affiliated center between 12/2008 and 01/2020. Included were singleton pregnancies complicated by GDM, for which placental histopathological examination was performed. Obstetric, neonatal and placental outcomes were compared between pregnancies following IVF and unassisted pregnancies. Placental lesions were categorized according to the "Amsterdam" criteria.

RESULTS

Included were 688 deliveries with a diagnosis of GDM with placental examination - 69 IVF pregnancies (IVF group) and 619 unassisted pregnancies (control group). The IVF group was characterized by a significantly higher maternal age and higher rate of nulliparous women - 60.8% vs. 32.9%, p < 0.001. There were no differences in GDM type between the study groups - about two thirds of cases were GDMA1 and on third GDMA2. A higher incidence of preeclampsia was noted in the IVF group - 17.3% vs. 9.3%, p = 0.03, with no difference in cesarean deliveries and birthweight. IVF deliveries were characterized by a significantly higher rate of adverse neonatal outcomes - 18.8% vs. 8.8%, p = 0.008, although this did not attain significance after adjustment to gestational age. No differences were noted in placental histology between the groups.

DISCUSSION

GDM in IVF is associated with a significantly higher rate of adverse neonatal outcomes, as compared with non-assisted pregnancies complicated by GDM. Placental histology does not shed light on these clinical associations.

Immunoendocrine Dysregulation during Gestational Diabetes Mellitus: The Central Role of the Placenta

Gestational Diabetes Mellitus (GDM) is a transitory metabolic condition caused by dysregulation triggered by intolerance to carbohydrates, dysfunction of beta-pancreatic and endothelial cells, and insulin resistance during pregnancy. However, this disease includes not only changes related to metabolic distress but also placental immunoendocrine adaptations, resulting in harmful effects to the mother and fetus. In this review, we focus on the placenta as an immuno-endocrine organ that can recognize and respond to the hyperglycemic environment. It synthesizes diverse chemicals that play a role in inflammation, innate defense, endocrine response, oxidative stress, and angiogenesis, all associated with different perinatal outcomes.